I'll check it out when i get out of school. I didn't even bother looking at it, sorry.

I find it's easy to read the Owner's manual when i'm sitting on the Throne.
Get in a habit to read the Owner's manual of everything you purchase...from electronics to cars to guns.
All the basic questions are answered in the owner's manual

a) I like having all 290 at the ready
b) I don’t wear a tin foil hat with respect to the manufacturers recommendation
c) if I really couldn’t afford the extra $250 / year, then I would have opted for the Accord V6 instead of the TLX V6 (could probably save >$250/year in insurance premiums by getting the AV6.)

There's so many arguments to this conversation it's beating a dead horse. If you're debating putting in regular or premium in the TLX then you should've bought a different brand car or at least consider cutting expenses elsewhere to put premium in your TLX. I put premium gas because I bought an entry-level luxury vehicle knowing I'd be paying premium price for just about everything and knowing I can afford it (not to mention it is what is recommended by Acura).

There's so many arguments to this conversation it's beating a dead horse. If you're debating putting in regular or premium in the TLX then you should've bought a different brand car or at least consider cutting expenses elsewhere to put premium in your car. I put premium because I bought an entry-level luxury vehicle knowing I'd be paying premium price for just about everything and knowing I can afford it.

will putting in premium fix the jerkiness or hesitation while driving it?

will putting in premium fix the jerkiness or hesitation while driving it?

I am no expert on this subject, but know the basics (I think. If I am wrong, someone please correct me)

The difference between the engine of the TLX and an Accord are the compression ratios. The compression ratio in the Accord is lower, so regular fuel will do. The compression ratio in the TLX is higher, where regular fuel will get the job done, but it could possibly result in engine knock, where the fuel ignites from compression versus igniting from the spark plugs, where it should ignite. Since the compression ratio in the TLX is high, Acura strongly recommends premium. What alot of people notice with putting regular fuel in their TLX, or any Acura in general; slower throttle response and lower fuel economy. Putting in premium fuel may fix the hesitation, but that sounds more like a transmission issue or the ZF9 changing gears pretty slowly.

The sensors in today's cars do a good job sensing what type of gas we put in our cars and it certainly can help reduce engine knock, but it may not completely reduce it. In a pinch it is safe to use regular fuel in the TLX, but the long term effects are the real concern. You save anywhere from $4-$8 filling up with regular fuel vs premium fuel, but if your engine needs significant repairs down the line, all that money you saved is being dumped back in towards the repair.

Personally, I bought this car knowing I'd be using premium fuel because that comes with the brand. If I knew I couldn't afford premium fuel then I would've gone to Honda or some other brand. I could easily save the $300-$350 a year in other expenses while continuing to give my car the gas that is recommended from the manufacturer. Again, this topic has been discussed hundreds of times on this board alone, put what you can afford. However, if you're struggling to fork over the extra $300-$350 in fuel each year, then maybe the TLX wasn't the right car for you in the first place.

Again, the compression ratio is the same 11:6 to 1 as in the Pilot / Odyssey (very same engine) for which regular is RECOMMENDED. The difference is giving up about 3% of ultimate engine power, hardly noticeable even if (I tested it many times). Detonation is no longer an argument with direct-injected engines. When did you hear the last time that an engine is destroyed because of detonation? In the last 15 years, I don't remember having heard of any.

In USA gas costs are lower and the delta between premium and regular is less than Canada. Here it represents about $400/year. So, regular for me (and Acura warranty covers it all).

There's so many arguments to this conversation it's beating a dead horse. If you're debating putting in regular or premium in the TLX then you should've bought a different brand car or at least consider cutting expenses elsewhere to put premium in your TLX. I put premium gas because I bought an entry-level luxury vehicle knowing I'd be paying premium price for just about everything and knowing I can afford it (not to mention it is what is recommended by Acura).

I am no expert on this subject, but know the basics (I think. If I am wrong, someone please correct me)

The difference between the engine of the TLX and an Accord are the compression ratios. The compression ratio in the Accord is lower, so regular fuel will do. The compression ratio in the TLX is higher, where regular fuel will get the job done, but it could possibly result in engine knock, where the fuel ignites from compression versus igniting from the spark plugs, where it should ignite. Since the compression ratio in the TLX is high, Acura strongly recommends premium. What alot of people notice with putting regular fuel in their TLX, or any Acura in general; slower throttle response and lower fuel economy. Putting in premium fuel may fix the hesitation, but that sounds more like a transmission issue or the ZF9 changing gears pretty slowly.

The sensors in today's cars do a good job sensing what type of gas we put in our cars and it certainly can help reduce engine knock, but it may not completely reduce it. In a pinch it is safe to use regular fuel in the TLX, but the long term effects are the real concern. You save anywhere from $4-$8 filling up with regular fuel vs premium fuel, but if your engine needs significant repairs down the line, all that money you saved is being dumped back in towards the repair.

Personally, I bought this car knowing I'd be using premium fuel because that comes with the brand. If I knew I couldn't afford premium fuel then I would've gone to Honda or some other brand. I could easily save the $300-$350 a year in other expenses while continuing to give my car the gas that is recommended from the manufacturer. Again, this topic has been discussed hundreds of times on this board alone, put what you can afford. However, if you're struggling to fork over the extra $300-$350 in fuel each year, then maybe the TLX wasn't the right car for you in the first place.

Just my .02

Thank you for your response. I've gotten my transmission replaced once and it is kinda better. not a lot of jerkiness just hesitation is still there. I'll be sure to start putting premium.

Again, the compression ratio is the same 11:6 to 1 as in the Pilot / Odyssey (very same engine) for which regular is RECOMMENDED. The difference is giving up about 3% of ultimate engine power, hardly noticeable even if (I tested it many times). Detonation is no longer an argument with direct-injected engines. When did you hear the last time that an engine is destroyed because of detonation? In the last 15 years, I don't remember having heard of any.

In USA gas costs are lower and the delta between premium and regular is less than Canada. Here it represents about $400/year. So, regular for me (and Acura warranty covers it all).

I would not hang my hat on its the same as the PILOT. The engines might be physically the same but IMHO they have different tunes. Not unlike my 440 which has the same compression ratio & is physically the same as the base engine but more horsepower. This is due to the factory MPPK power kit that changes the ECU programming with a more advanced ignition curve that requires more octane.

I believe the TLX engine is a PILOT engine with a factory performance tune as standard.

Or water. There's a lot of hydrogen and oxygen in water. Both of which are flammable.

Heh heh. I put in 93, but when I drive in reverse, it's only 39. So if you drive a lot in reverse, it's better to put in 87.

Kidding guys. In the end, I just go with what's recommended. To be fair to the "tin foil hat" guys, I think for them, it's more of a matter of optimization / efficiency rather than not being able to afford premium.

I have done much worse, believe.me. My "policy" is that if you don't use it or benefit from it, it is a waste. Nothing to do with affordability.

I agree with this. My TLX has no issues with regular fuel. My 07 type S knocked and pinged terribly the one time I put regular grade in it and didn't idle well on regular grade so I always used premium in it. I also had a bmw that couldn't idle smoothly on regular so I always used premium in it. Premium recommended is not the same as premium required. For me as well it's not affordability but how the engine performs that makes me go with one over the other. I may try a tank of premium to see if there is any difference in performance. I do know that the engine management system is supposed to adjust to avoid knocking and pinging but the type S engine that was not the case.

One plus of the TLX is that is does run fine on regular grade with no knocking or pinging which is a signature of too low octane for the engine.

I still don't know why this discussion always shows up, is Acura not premium enough to avoid using premium gas?
Honestly if you must save the $5 in gas per week, you shouldn't be looking at luxury cars since they always ask for better gas. If reliability is the #1 reason to go with Acura, shouldn't a clean fuel burning engine be the top thing on your list?

Gas is the last thing I think about with cars, just put what it says.

Last edited by pyrodan007; 02-13-2018 at 08:54 PM.

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I still don't know why this discussion always shows up, is Acura not premium enough to avoid using premium gas?
Honestly if you must save the $5 in gas per week, you shouldn't be looking at luxury cars since they always ask for better gas. If reliability is the #1 reason to go with Acura, shouldn't a clean fuel burning engine be the top thing on your list?

Gas is the last thing I think about with cars, just put what it says.

This discussion finds itís way to literally EVERY forum I have ever been on/briefly creeped. I think itís so prevalent on this forum for two reasons, one because Acura is an entry level premium brand and a lot of people coming to Acura for the first time were used to using regular for a majority of their lives so they stop and think about how important it is (not judging anyone whatsoever), the second reason is these engines are identical to their Honda counterparts and in some cases almost exactly the same (Accord and RDX have a 1hp difference and yet Acura recommends premium for the RDX...really?).

All my driving career (8/9 cars) most of my cars have required premium so when it comes to buying a car the last thing that comes to mind is what kind of gas I need because Iím used to it now. However my father has never had a car that needed premium so when he goes with me places and I stop to fill and put premium he always scoffs at it. So it is a matter of perspective.

I agree with this. My TLX has no issues with regular fuel. My 07 type S knocked and pinged terribly the one time I put regular grade in it and didn't idle well on regular grade so I always used premium in it. .

Similar experience with my BMW I6. It didn't tolerate regular gas at cold. The J35Y6 (shared TLX/Pilot/Ridgeline/Odyssey) was designed to run on regular, right from the start.

I was just wondering what gas should I put in because my transmission is screwing up. Already got it replaced once and its still acting up. Hesitation when I press the gas pedal, jerks when coming to a stop, etc. I'll put in 91 octane next time and let you guys know if anything changes!

Similar experience with my BMW I6. It didn't tolerate regular gas at cold. The J35Y6 (shared TLX/Pilot/Ridgeline/Odyssey) was designed to run on regular, right from the start.

Stop spreading false information.

Yes the J35Y6 is in the TLX and various Honda models, they however weren't designed for "Precision Crafted Performance". The TLX has different camshafts, intake valves & ECU tune to take the J35Y6 to peak performance.

Saying the J35Y6 was designed to run regular from the start is correct, for the Honda models. The TLX on the other hand, was designed to run 91.

This site has been based off quality information for many years & is why we're one of the top automotive forums on the internet. We don't need ppl spewing false information based off their opinion, especially with no facts to back up their claims.

the second reason is these engines are identical to their Honda counterparts and in some cases almost exactly the same (Accord and RDX have a 1hp difference and yet Acura recommends premium for the RDX...really?).

Its a weight & usage differential. They RDX is about 700LBS heavier to start before both are loaded with people & stuff. Same engine pulling different weights the heavier one will knock first. In addition to the fuel recommendation the RDX also has it static compression ratio dialed back to 10.5 close but still more then the Accords 10.3 but less then the TLX 11.5. The reduced CR also helps push off knock onset of knock on a heavier car.

I would expect with an 11.5CR the RDX would be a premium mandatory.

Still all falls back on the on the internet experts vs the engineers with designed & built the engine as to who is better to recommend fuel. For $5.00 a tank why is this even a question.

Last edited by BEAR-AvHistory; 02-14-2018 at 10:59 AM.

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Its a weight & usage differential. They RDX is about 700LBS heavier to start before both are loaded with people & stuff. Same engine pulling different weights the heavier one will knock first. In addition to the fuel recommendation the RDX also has it static compression ratio dialed back to 10.5 close but still more then the Accords 10.3 but less then the TLX 11.5. The reduced CR also helps push off knock onset of knock on a heavier car.

I would expect with an 11.5CR the RDX would be a premium mandatory.

Still all falls back on the on the internet experts vs the engineers with designed & built the engine as to who is better to recommend fuel. For $5.00 a tank why is this even a question.

Get your logic out of here! You mean to tell me that we're supposed to take into ALL of the variables of the car and not JUST one singular similarity?!

And now you know that all J35Y6 have the same CR, even the ones that run on regular.

Don't know much about the brand but am OK with CR's. If the post is correct & the engine has different cams there can be a very real difference is octane requirements even if the Static Compression ratio is the same.

Camshaft overlap & duration effect the dynamic compression ratio so if they are different the onset of knock will be different all else equal. Static is just a physical measurement of the swept cylinder volume full piston down vs full piston up. The fuel never sees this ratio.

Dynamic Compression ratio always lower then the static compression ratio. It is the compression ratio after the intake valve actually closes & determines about how the engine will perform with a particular cam and octane.

Ignition timing advance & curve shape also are a factor in octane requirement. These perameters can also stand alone to effect knock fuel economy & power.

Just as an aside for flexibility. With the same cams I can run a number of different tunes in the COBRA because the ECU can effectively CHANGE cam timing. This change in timing effects the SCR.

One tune long duration early intake opening will simulate a 66 427 Le mans race engine with a very rough idle. Another is street performance for 93 octane & the third is track for 100 octane. Takes about 10 minutes with a handheld to switch tunes.

Cant imagine HONDA does not do this with their ECU on how Vtec is employed.

Last edited by BEAR-AvHistory; 02-14-2018 at 02:58 PM.

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Its a weight & usage differential. They RDX is about 700LBS heavier to start before both are loaded with people & stuff. Same engine pulling different weights the heavier one will knock first. In addition to the fuel recommendation the RDX also has it static compression ratio dialed back to 10.5 close but still more then the Accords 10.3 but less then the TLX 11.5. The reduced CR also helps push off knock onset of knock on a heavier car.

I would expect with an 11.5CR the RDX would be a premium mandatory.

Still all falls back on the on the internet experts vs the engineers with designed & built the engine as to who is better to recommend fuel. For $5.00 a tank why is this even a question.

I feel like you assumed I was saying itís fine to put regular in the RDX because it almost makes the same power as the accord. I was just saying what I think peopleís thought process is on it. I would without a doubt put premium (and have in my RDX and MDX) in any car that even recommended it let alone required it. I sometimes even put 94 in as well, itís only a couple cents more than 91 so why not?

I feel like you assumed I was saying itís fine to put regular in the RDX because it almost makes the same power as the accord. I was just saying what I think peopleís thought process is on it. I would without a doubt put premium (and have in my RDX and MDX) in any car that even recommended it let alone required it. I sometimes even put 94 in as well, itís only a couple cents more than 91 so why not?

In our part of the country, the RON options are 87/Regular, 89/MidGrade, and 93/Premium. I don't think I've seen 91 RON or 94 RON fuel anywhere within a thousand-miles of New England.

I feel like you assumed I was saying itís fine to put regular in the RDX because it almost makes the same power as the accord. I was just saying what I think peopleís thought process is on it. I would without a doubt put premium (and have in my RDX and MDX) in any car that even recommended it let alone required it. I sometimes even put 94 in as well, itís only a couple cents more than 91 so why not?

No problem. RDX is heavy so I would go with the recommended fuel Premium. Point I would make is even identical engines subjected to different expected loads can require different grades of gas. Also that the static compression ratio is an interesting number but not the operative number.

Why people wet their pants over an 11.5 to one vs a 10.5 or other lower number is from the old muscle car days when the big dogs ran 11.5 & the others ran 9 9.5 10.0 etc.

In our part of the country, the RON options are 87/Regular, 89/MidGrade, and 93/Premium. I don't think I've seen 91 RON or 94 RON fuel anywhere within a thousand-miles of New England.

Canada my friend

We typically get 87, 89, 91 in most stations. Some will offer 94 as well. Never seen 93 ever. Very interesting.

Quote:

Originally Posted by BEAR-AvHistory

No problem. RDX is heavy so I would go with the recommended fuel Premium. Point I would make is even identical engines subjected to different expected loads can require different grades of gas. Also that the static compression ratio is an interesting number but not the operative number.

Why people wet their pants over an 11.5 to one vs a 10.5 or other lower number is from the old muscle car days when the big dogs ran 11.5 & the others ran 9 9.5 10.0 etc.

There is a lot more involved then the raw SCR#

Yeah no I totally get it and agree. I mean if the difference between regular and premium was massive it might be worth a pause but itís a few dollars a tank to get the full performance so why the hell not.

Pretty sure the whole east cost runs 87/89/93 + some extras. One of my stations sells 100 octane in addition to the main 3 grades others have the main three + 90 no ethanol. Auto diesel is also pretty common but not at every station. In Raleigh there are no E-85 stations anymore.